Testing effects of reproduction on stress and mortality

测试生殖对压力和死亡率的影响

• 批准号: 7127805
• 负责人: John D. Hatle
• 金额: $ 16.65万
• 依托单位: UNIVERSITY OF NORTH FLORIDA
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7127805
• 关键词: Orthoptera; antioxidants; biological models; densitometry; enzyme activity; enzyme linked immunosorbent assay; germ cells; heat shock proteins; hemolymph; longevity; nutrient bioavailability; nutritional epidemiology; ovariectomy; ovary; oxidation; polymerase chain reaction; radioimmunoassay; reproduction; stress; superoxide dismutase

DESCRIPTION (provided by applicant): This study will determine the direct effects of the adult ovary on mortality rate in an insect model organism. Reproduction may shorten lifespan in at least two ways: limited nutrients may be allocated to reproductive processes instead of the soma, or reproduction may create direct negative effects on longevity that are independent of nutritional allocation (e.g., release of aging hormones). The effects of calorie restriction on longevity are well studied. The contributions of reproduction that are independent of nutrition are not well understood. In this project, I examine the model of direct effects of reproduction on longevity. This model posits that when germ-line tissue is intact it directly reduces the individual's ability to resist cellular stress or minimize oxidation, thereby increasing age-specific mortality rate independently of nutrition. Grasshoppers are excellent models for this approach to aging because they are large enough for tracking individuals and analyzing multiple tissues, but are shorter-lived (approximately 80 days) and cheaper than mice. Plasticity of reproduction in grasshoppers is well characterized; this proposal extends these studies to plasticity of stress tolerance and age-specific mortality. Aim #1 will test whether ovariectomized females have higher constitutive levels of heat shock protein 70 and superoxide dismutase activity. The model of direct effects on reproduction predicts higher Hsp70 levels and superoxide dismutase activities. Aim #2 will test whether the ovary decreases age-specific mortality rate independently of nutritional allocation to vitellogenesis. The model of direct effects of reproduction on longevity predicts the ovary will decrease mortality rate with decreasing vitellogenesis. Aim #3 will test whether ovarian effects on mortality rate are linked to nutrient allocation. The model of direct effects of reproduction on longevity predicts that ovarian effects do not act through nutritional allocation. Understanding the basic biology of aging is critical to the health care of the nation. Reproduction is known to reduce longevity, but how this can occur independently of nutrition is not clear. Using an insect model, this proposal will examine whether the ovary decreases life-span, without the confounding affects of nutritional distribution. Ovarian control of stress proteins and anti-oxidants will also be tested. Last but not least, this grant will have a profound effect on the research environment in biology at the University of North Florida.

描述（由申请人提供）：本研究将确定成虫卵巢对昆虫模型生物死亡率的直接影响。繁殖可能至少以两种方式缩短寿命：有限的营养可能会分配给繁殖过程而不是体细胞，或者繁殖可能会对寿命产生与营养分配无关的直接负面影响（例如，释放衰老激素）。热量限制对长寿的影响已得到充分研究。与营养无关的生殖贡献尚不清楚。在这个项目中，我研究了生殖对寿命的直接影响的模型。该模型假设，当种系组织完好无损时，它会直接降低个体抵抗细胞应激或最小化氧化的能力，从而增加与营养无关的年龄特异性死亡率。蚱蜢是这种衰老方法的绝佳模型，因为它们足够大，可以追踪个体并分析多个组织，但寿命较短（约 80 天），而且比小鼠便宜。蚱蜢繁殖的可塑性已得到很好的表征；该提案将这些研究扩展到压力耐受性和特定年龄死亡率的可塑性。目标 #1 将测试卵巢切除的女性是否具有较高的热休克蛋白 70 和超氧化物歧化酶活性的组成水平。对生殖的直接影响模型预测更高的 Hsp70 水平和超氧化物歧化酶活性。目标#2 将测试卵巢是否降低年龄特异性死亡率，而与卵黄发生的营养分配无关。生殖对寿命的直接影响模型预测，卵巢将随着卵黄发生的减少而降低死亡率。目标#3将测试卵巢对死亡率的影响是否与营养分配有关。生殖对寿命的直接影响模型预测卵巢效应不会通过营养分配发挥作用。了解衰老的基本生物学对于国家的医疗保健至关重要。众所周知，繁殖会缩短寿命，但这种情况如何独立于营养而发生尚不清楚。该提案将使用昆虫模型来检查卵巢是否会缩短寿命，而不会受到营养分配的混杂影响。卵巢对应激蛋白和抗氧化剂的控制也将受到测试。最后但并非最不重要的一点是，这笔资助将对北佛罗里达大学的生物学研究环境产生深远的影响。